The descending

aortic hiatus thoracic portion abdominal portion

Thoracic cavity Abdominal cavity

At the level of the caudal lumbar vertebrae it divides into its terminal branches: A- 2 External iliac a. B- 2 Internal iliac a. C- Median sacral a

Thoracic aorta and

• Branches of the thoracic aorta:- 1) Dorsal intercostal : thoracic and abdominal wall, spinal cord. 2) Bronchoesophageal : a- Bronchial branches bronchial tree, b- Ephageal branches esophagus, 3) Costoabdominal artery abdominal wall 4) Cranial phrenic artery diaphragm present in the horse only abdominal aorta

Parietal branches Visceral branches

segmental arteries, 1.Phrenico-abdominal which are called artery 2.Celiac artery, 3.Cranial mesenteric artery 4.Renal arteries), 5.Testicular / ovarian arteries 6.Caudal mesenteric artery

Viceral branches of abdominal aorta

1) Caudal phrenic artery present in all the domestic mammals, other than the horse:diaphragm. 2) Celiac artery, • Splenic artery , 1- Splenic branches (a. lienalis), 2- Left gastroepiploic artery 3- Short gastric branches

• Left gastric artery 1- Visceral branch 2- Esophygeal branch

• Hepatic artery , 1- Hepatic branches 2- Right gastric artery (pyloric region) 3- Right gastroepiploic artery 4- Cranial Pancreaticodudenal artery

3- Cranial mesenteric artery • It gives the following branches: 1- Caudal pancreaticoduodenal artery 2- Jejunal arteries , 3- , A- Cecal arteries ((medial and lateral cecal branch) B- Heal arteries (ilial a), C- Colic branch (to the ventral u-shape of the ascending colon). 4- (to the dorsal u-shape of the ascending colon), 5- (to the transverse colon),

3- Caudal mesenteric artery

1- .

2- Cranial rectal artery.

Termination of the abdominal aorta

1- Right and left external iliac artery 2- Right and left 3- . External iliac artery

1. Uterine artery ( only mare), 2. Deep circumflex iliac artery 3. Deep : A- Pudendoepigastric arterial trunk - External pudendal artery. (, mammary gland) - Caudal epigastric artery. (abdominal muscles). B- medial circumflex femoral artery 4- Femoral artery, which passes through the femoral canal and gives: 1) Lateral circumflex femoral artery, 2) Caudal femoral artery, 3) Saphenous artery, 4) Descending genicular artery, 5- Popliteal artery: 1) Caudal tibial artery, 2) Cranial tibial artery: A- Dorsal pedal artery B- Dorsal metatarsal artery: 1- Lateral plantar digital artery 2-Medial plantar digital artery

Internal iliac artery • The internal iliac artery provides blood supply to the pelvic viscera and the walls of the pelvic cavity, including the lumbar muscles and the overlying muscles of the gluteal region. • It is one of the terminal branches of the aorta and in the horse the median sacral artery can arise either from the left or the right internal iliac artery. The median sacral artery gives origin to segmental branches.

A- Lumbar arteries: to the vertebral column and associated structures (Opposite the 6th lumbar vertebra) divides into: B- Caudal gluteal artery: 1. Cranial gluteal artery: (it exits through the greater sciatic foramen) supply the dorsolateral wall of the and the croup. 2. : (arising either from the caudal or cranial gluteal artery), it leaves the pelvic cavity together with its satellite and nerve by the obturator foramen and gives the middle artery of the penis in male and middle artery of the clitoris in female. 3. : to deep lumbar muscles C- : to the pelvic viscera. 1 - Uterine artery: not found in mare 2 - : In the stallion, it releases the small artery of the deferent duct In both sexes, it gives the cranial vesical artery and ends as the round ligament of the urinary blaader. 3 - (prostatic artery in the male): 1- Branch to deferent duct or uterine branch 2- Caudal vesical artery 3- Ureteric branch 4- Urethral branch 5- 4- Ventral

5 - Caudal rectal artery

6- Vestibular artery or artery of the penis

7- Dorsal artery of the penis left lateral views of the male and female arterial supply to the canine pelvis. 1 - aorta 2 - external iliac 3 - Internal iliac 4 - median sacral 5 - cranial gluteal 6 - caudal gluteal 7 - Internal pudendal 8 - ventral perineal 9 – penile 10 - caudal superficial epigastric 11 - caudal deep epigastric 12 - artery of the ductus deferens 13 - urogenital 14 - testicular 15 - ovarian 16 - uterine 17 - pudendoepigastric trunk which gives 18 - cranial rectal 19 - caudal rectal 20 - obturator 21 - umbilical 22 - vesical